The invention relates to a textile substrate that has water-wicking properties and comprises wool as well as at least one other fiber. Such substrates are characterized by excellent ability to absorb and wick off water vapor and water. They are suitable in particular for seat coverings, especially coverings on elongated seats that are used without interruption, as in cars, buses, trains and aircraft, as well as for office chairs, wheelchairs, etc. The good wicking of moisture from the fabric surface helps to achieve good sitting comfort, because the seat covering does not become damp even if the seat has been occupied for a long time, but instead always feels dry and thus guarantees xe2x80x9cclimatized sittingxe2x80x9d.
From European Patents 356708, 455848 and 685583 there are known textile substrates of the class in question, each of which discloses a proportion of natural fibers, especially wool and ramie. In this connection, this proportion of natural fibers ranges between 65 and 85 wt % of wool and ramie (European Patent 356708), it amounts to at least 40 wt % of wool and at least 5% of ramie (European Patent 455848) or it comprises at least 40% of wool and at least 15% of ramie, but the two together always exceed 85 wt % (European Patent 685583).
Whereas European Patents 356708 and 455848 each require a proportion of synthetic fibers as wellxe2x80x94whether for the purpose of water wicking or of better dyeabilityxe2x80x94European Patent 585583 discloses a textile substrate for seat coverings, a woven fabric, a single-thread knitted fabric or a multi-thread knitted fabric, which contains a mixed yarn comprising 80 wt % of wool and 20 wt % of ramie in the warp and ramie threads in the weft.
Initially it seemed extremely doubtful whether extensive or even total avoidance of synthetic fibers would not restrict the creative options of the material designer too much and in particular detract from the excellent properties of known textiles of the class in question as regards water absorption and wicking. The first problem is less serious, and can be circumvented by appropriately adapted color schemes. For fluid transport, however, it seemed indispensable for long-term purposes to provide a relatively high proportionxe2x80x94at least 15 wt %xe2x80x94of synthetic fibers, preferably polyesters, since their hydrophobic properties have been credited with fluid transport over relatively long distances. Surprisingly, however, it had been found that the same function is achieved by ramie fiber when it is present in adequate concentrationxe2x80x94at least 15 wt %xe2x80x94in the substrate. Judging by its chemical compositionxe2x80x94degummed ramie comprises substantially cellulosexe2x80x94this behavior could not have been expected. The fact that ramie is also able to transport water over relatively long distances was attributed to strong capillary action, which in turn is due to the fact that the ramie fibers form tubes which are additionally provided in the interior with longitudinal grooves. As a logical development, the requirement was established that the ramie content in a textile substrate must be at least 15 wt % in order to satisfy the strict requirements of wicking of moisture from the fabric surface and to guarantee good sitting comfort.
Surprisingly it has now been found thatxe2x80x94if the ramie fibers are left out and replaced by viscose rayon fibersxe2x80x94practically equivalent wicking of moisture from the fabric surface can nevertheless be maintained.
These inventive textiles comprise at least extensively, but preferably exclusively, natural fibers, and can therefore be disposed of very safely from the environmental viewpoint: The inventive textiles can be chopped to pieces, heaped up and stored at sufficiently high humidity and temperature; they decompose completely and thus can be composted properly.
In any case the discovery of the fact that viscose rayon fibers remove water over long distances forms the basis for a surprisingly simple solution of the object of providing, for seat coverings, an alternative textile substrate that not only is extremely comfortable, in that it always feels dry even after prolonged, uninterrupted use under adverse conditions such as high temperatures and high relative humidity, but also it causes very little environmental pollution and in particular can be effectively disposed of and decomposes under suitable conditions with the least possible residues that must be disposed of.